Catalyzing Innovation: WWRP activities and future directions
- the next 7 years (2016-2023)

The World Weather Research Programme (WWRP) was established in 1998 to address the growing societal impacts of a range of high-impact weather events over various time- and space scales by consolidating advances in prediction research efforts made by individual working groups and projects. Since then WWRP had initiated, endorsed and helped to spin-up inter- national and national research projects, related to weather prediction. In 2003, WMO established an international atmospheric research and development programme, The Observing system Research and Predictability Experiment – THORPEX which ended in 2013. THORPEX provided the framework for strong international collaborations in field experiments, exploitation of observation technologies or usage of ensemble techniques. In 2014, the first World Weather Open Science Conference (WWOSC-2014) was held in Montreal, Canada. This major conference was designed to act as an international stimulus for weather related science and its future. For the first time, it brought together the whole research community to examine the rapidly changing scientific and socio-economic drivers of weather science. The experts reviewed the frontiers of knowledge, discussed the state-of-the-art and the future evolution of weather science, as well as of the related environmental services and how these need to be supported by research. Looking forward to setting the stage for the future weather enterprise is the role WWRP is playing, connecting the past achievements on weather science with new societal challenges seamlessly linking weather, environmental and climate enterprises. Bringing the future closer means working closer with young scientists, supporting a new generation of earth system scientists and taking advantages of fresh ideas. In 2016, the 68th Executive Council of WMO endorsed WWRP’s Implementation Plan for 2016-2023. Developed along the four main societal challenges proposed by CAS (i.e. High-impact Weather, Water, Urbanization and Evolving technologies) the new implementation plan builds upon new challenges for the weather science. As weather science advances, critical questions are arising such as about the possible sources of predictability on weekly, monthly and longer time-scales; seamless prediction; the development and application of new observing systems; the effective utilization of massively-parallel supercomputers; the communication, interpretation, and application of weather-related information; and the quantification of the societal impacts. The science is primed for a step forward informed by the realization that there can be predictive power on all space and time-scales, arising from currently poorly understood sources of potential predictability.

INMET develops a Numerical Weather Prediction System for the Rio 2016 Olympic and Paralympic Games

By invitation of the Rio 2016 Olympic Games Organizing Committee, the National Institute of Meteorology (INMET) acted as coordinator of the group responsible for providing weather data for the Rio 2016 Olympic and Paralympic Games. In preparation for the 2016 Games, an INMET staff and a representative of the Brazilian Navy visited London during the 2012 Olympic Games and attended a number of activities organized by the UK Met Office as part of the Brazilian Government Observers Program. For Rio 2016, INMET used the COSMO model, with 1km resolution, updated four times a day (00, 06, 12 and 18 UTC), with hourly outputs for two areas: Guanabara Bay – where sailing competitions were held and a pre-determined area in the city of Rio de Janeiro.

Figure 1 illustrates the wind forecast measured at standard height of 10 meters above the ground for the Guanabara Bay area. The red crosses represent sailing lanes for the competition.

Figure 2 illustrates the expected precipitation for the Rio de Janeiro area

Article contributed by Marcia Seabra (INMET)

CPTEC/INPE develops ocean and air quality forecast systems
for the RIO 2016 Games

The Center for Weather Forecasting and Climate Studies of the National Institute for Space Research (CPTEC/INPE) had the responsibility to develop and implement the state-of-the-art operational system for real-time monitoring and forecasting the ocean conditions for sailing regatta, marathon swimming and triathlon. The forecasting ocean system was composed of oceanic and wave models implemented to predict sea conditions in the Guanabara Bay. Operational wave and wind forecast verification were included to evaluate the forecast quality compared with buoy data and as a tool
for short-range forecasting (Fig 1).

Furthermore, CPTEC/INPE provided air quality forecasts for the Metropolitan Region of Rio, using the Brazilian developments on the Regional Atmospheric Modeling System (BRAMS) in high horizontal resolution. The development of the air quality forecast system required the addition of regional source emissions from vehicle fleet and the implementation of an urban parameterization in BRAMS to better represent land-surface-atmosphere feedbacks in an urban area. The validation of the ozone and PM2.5 forecasts showed model in general had good performance but underestimates concentration in some air pollution episodes. The main challenge of the preparation of the weather services for Olympics was the very short-time to deliver informations and high horizontal and temporal resolution. It was a complex issue to provide forecasts on time to be used quickly. This effort required more than 30 specialists from different sectors of CPTEC/INPE (Image below).

The meteorological services provided in so complex environment like Rio highlighted the importance of communication between scientific community and end-users living in urban areas. The access of weather and air quality information by the public can help the protection especially those living in the urban areas. The ocean forecasting system can also be extended to other shore areas along the Brazilian coast exposed to occurrence of extreme events of wave conditions, flooding, storm surges and coastal erosion.

Article contributed by Sergio Ferreira et. al. (CPTEC/INPE)

Anomalous Precipitation Patterns in the Asian Monsoon Region
during the 2015-2016 El Nino

The 2015-2016 El Nino is one of so-called three mega-El Nino events since 1950, which warmed the equatorial central and eastern Pacific with extending 3℃. It has exerted a significant impact on the anomalous precipitation pattern in the Asian monsoon region in the second year after the onset of the event.

Figure 1 shows the distribution of precipitation anomaly percentage in the Asian monsoon region in the summer (JJA) of 2016. It can be clearly seen that nearly entire Asian monsoon region has become wetter than the climatological condition. Especially, one can see two extremely anomalous precipitation belts with anomaly percentage greater than 60%: the tropical one extending from the central India across Southeast Asia to the Yangtze River valley of China and West Japan; and the mid-latitude one extending from the central Asia across Northwest China to North China. In between, one relative dry zone in the subtropical region in China and Korea peninsula may be observed.

For the occurrence of the tropical anomalous precipitation belt, an anomalous subtropical high developed and is persistently located in West-Pacific in June and July, 2016 (Figure 2(a) above)(Wang and Zhang, 2002). It can greatly enhance the northward moisture transport from the ocean to the Yangtze River valley and west Japan, on one hand, and on other hand, the westward moisture transport all the way to Southeast Asia and the central India.

Further, in August (Figure 2(b) above), the westward moisture transport having its origin in the subtropical sea regions of Northwest Pacific continued to support the persistence of this tropical precipitation belt which is really the location of ITCZ. The above analysis clearly lends support the conclusion that the El Nino event can greatly increase the moisture transport from the ocean and provide a more abundant moisture supply for large-scale continental precipitation, thus improving water resource use over land.

The Young Earth System Scientists (YESS) community unifies international and multidisciplinary early career scientists (ECS - an undergraduate or postgraduate (Masters/PhD) student or a scientist who has received his or her highest degree (BSc, MSc, or PhD) within the past 5 years) in a powerful network, providing a voice and leverage for a better future to serve society. YESS is organized from the bottom up, run by and for ECS through an efficient communication platform to coordinate activities both internationally and locally. We welcome members from a wide range of scientific backgrounds, creating a synergy between researchers in natural and social sciences who represent the future of Earth system science.

The YESS community is happy to announce that the YESS paper 'Earth System Science Frontiers - an ECS perspective' has been accepted for publication in the Bulletin of the American Meteorological Society (BAMS). In the paper, an active group of Young Earth System Scientist members describe their long-term vision of the frontiers of Earth system science, paving the pathway towards an integrated understanding of the Earth system. The paper is a result of the World Meteorological Organization-supported Early Career Researchers Workshop in October 2015 and focuses on four frontiers: Seamless Earth system prediction, communication, user-driven science, and interdisciplinarity.

RESEARCH ISSUES

Improving Jet Stream Forecasts through Observational Experiment

Weather systems developing over the North Atlantic and hitting Europe are intimately related to large-amplitude meanders of the jet stream, known as Rossby waves. Characteristic weather patterns grow in concert with the waves, and the jet stream acts as a wave guide, determining the focus of the wave activity at tropopause-level. Rossby wave energy transfers downstream rapidly, amplifying troughs and ridges. Recent research has shown that forecast busts (where skill is much lower than usual) for Europe share a common precursor 5-6 days beforehand; a distinct Rossby wave pattern with a more prominent ridge (northwards displacement of the jet stream) across the eastern USA. The reasons for these forecast busts are not known, but it is hypothesised that the representation of diabatic (cloud and radiative heating) processes, over the USA and Atlantic, lowers the predictability in this situation. We need new observations within the waveguide at tropopause level with sufficient vertical resolution to resolve the detailed jet stream structure and quantify the diabatic processes acting as disturbances develop. We also need to connect these “upstream” observations with a comprehensive network of observations where the downstream weather impacts occur. An experiment tackling this inter-continental problem has just taken place: 16 Sep – 16 Oct 2016. NAWDEX is an initiative of WWRP, stemming from the THORPEX programme and part of the new High Impact Weather project. The experiment involved four research aircraft equipped with lidar, radar and dropsondes for measuring high resolution cross-sections of winds, temperature and humidity; 3 based from Iceland and the 4th from downstream from the UK. A comprehensive network of ground-based radar and lidar profiling stations ran continuously, including supersites in the UK and France, plus up to 400 additional radiosondes spanning northern high latitudes (45-65N) from the Japanese ship MV Mirai in the Bering Strait across Canada and the North Atlantic to western Europe. The value of widespread enhancement to the northern hemisphere observation network will be assessed in preparation for the WWRP Year of Polar Prediction (mid 2017 – mid 2019).

Image 1: Illustration of phenomena on the jet stream related to downstream propagation of wave activity and high impact weather (John Methven)

Image 2: Photo of the High Altitude and LOng Range (HALO)Research Aircraft that will operate from Iceland during NAWDEX, Credit: DLR, CC-BY 3.0

Article contributed by John Methven (University of Reading and co-chair of PDEF) et. al.

Do you know the challenges/opportunities of NWP applications
for nowcasting severe weather?

When a Numerical Weather Prediction (NWP) model is aimed for nowcasting applications, it must be tailored to meet the requirements of nowcasting. Among them, the assimilation of high-resolution data into a high-resolution model in a rapidly cycled fashion is perhaps on the top of the list. In recent years, several operational centers have shown progress in improved precipitation forecasting primarily due to the inclusion of radar observations in their data assimilation systems (see Figure below for an example).

However, great challenges remains. Below is a summary of four greatest challenges/opportunities facing the data assimilation and NWP community concerning the NWP applications for nowcasting severe weather:

Improved mesoscale networks. The current operational network can not satisfy the need for accurate mesoscale analysis/forecast. High-resolution observations, such as those from X-band radars, PBL profilers, lightning networks, and enhanced surface networks, can potentially improve the mesoscale and convective-scale observations and NWP-based nowcasting when properly assimilated into NWP models.

Computation requirement. In many operational centers, computation resources are mainly devoted to global models and the NWP-based nowcasting is still a low priority. Without adequate computing power, the NWP-based nowcasting can not be achieved operationally.

Model uncertainties. Improving the model parameterization schemes, especially the PBS schemes and microphysics schemes, can play an important role in improving the NWP-based nowcasting. On the other hand, ensemble-based data assimilation and prediction provides a practical way to measure the uncertainties of the model.

Further development of data assimilation techniques. Among many issues to be addressed in high-resolution data assimilation with rapid update cycles is the multi-scale balances, meaning that the synoptic-scale balance that supports the convective evolution is not damaged when adding convective-scale information through data assimilation of high-resolution observations.

PROGRESS OF WORK

An extreme rainfall event during SCMREX

A long-lived mesoscale convective system (MCS) produced extreme rainfall (451 mm in 16 h) over the coastal region of South China on 10 May 2013 during the Southern China Monsoon Rainfall Experiment (SCMREX). From midnight to early morning, convection was continuously initiated as southeasterly flows near the surface impinge on the east side of mesoscale mountains near the coastal lines and then moved northeastward, leading to formation of two quasi-stationary rainbands. From early morning to early afternoon, new convection was repeatedly triggered along a mesoscale boundary between precipitation-induced cold outflows and warm air from South China Sea and Gulf of Tokin, resulting in the formation of “band training” of several parallel rainbands that moved eastward. Local surface inhomogeneity, near-surface winds, warm advection in PBL from the ocean, and precipitation-generated cold outflows play important roles in initiating and maintaining the extreme rain-producing MCS.

(Figure above) Schematic diagrams of the back building, echo training, and rainband training associated with the extreme rain-producing MCS during its (a) early development and (b) mature stages. Shadings in red, orange, and green represent roughly the radar reflectivity values of 50, 35, 20 dBZ at 3km above mean sea level, respectively. Gray symbol near the southwest edge of the linear-shaped MCS in Fig. 1a represent a mountain. [Taken from Wang et al. (2014)]

The Mesoscale Verification Inter-Comparison over Complex Terrain (MesoVICT) project investigate characteristics of spatial verification methods for deterministic and ensemble forecasts of precipitation and wind over complex terrain. More importantly, MesoVICT takes observation uncertainty into account. Initial results presented at the 2nd MesoVICT workshop in September 2016 in Bologna, Italy, gave new insights on the properties of these measures which may result in further recommendations regarding their suitability. Next steps include i) testing on idealized geometric cases, ii) consideration of the impacts of complex terrain and iii) creation of an inter-comparison matrix describing attributes of the spatial verification methods. Participation is still open (contact: Eric Gilleland (ericg@ucar.edu))

(Figure above) Influence of observation uncertainty on the RMSE of wind speed at grid point Vienna at 3-hourly intervals for 20 to 22 June 2007 . Dark green: RMSE calculated from VERA reference run and COSMO-LEPS mean. Box plots represent changes in RMSE stemming from observation uncertainty represented by the VERA ensemble analysis. Note: RMSE fluctuates by a factor of two.

The Observing Research Prediction Experiment (THORPEX) Legacies and the Future of the World Weather Research Program (WWRP)

WWRP-THORPEX has improved predictive skill, advanced knowledge of processes that lead to high impact weather, and helped transfer the benefits of improved prediction to developing nations. These THORPEX outcomes provides the opportunity, if not the imperative, for the WWRP to profoundly advance the ability of operational centers to meet society’s needs. The THORPEX role in the International Polar Year, for example, provided a foundation for the Polar Prediction Projectand the Year of Polar Prediction(see figure below) that will enable the development of improved weather and environmental prediction services for polar regions. The global implications of Arctic warming ensure worldwide benefits.

THORPEX cooperation with the WCRP enabled the WWRP role in the Subseasonal to Seasonal Prediction Project, noting that the focus prior to THORPEX was mainly on short and medium range prediction. The High Impact Weather Project, another legacy project, couples the expertise of THORPEX with the other components of the WWRP and seeks dramatic increases worldwide in resilience to high impact weather through improvements in forecasts and advances in their communication and utility. This strategy follows the truly pioneering efforts of WWRP to incorporate applications and social science research. The success of these three projects and other future WWRP efforts will be increased through staying true to the founding WWRP strategy of staying focused on problems at the intersection of challenging science and operational needs allowing a paradigm shift in cooperation between forecast centers and the research community.

Figure above: The strategy and time-line for the Year of Polar Prediction that will take place
from mid-2017 to mid-2019.

David Parsons
Director, School of Meteorology
Mark and Kandi McCasland Chair Meteorology
Professor and former Chief, WWRP, WMO

FEATURED PROJECT

Probabilistic Forecasts and Civil Protection:
From seamless warnings to actions

The focus of the INCA-CE project (WMO Bulletin nº :Vol 65 (1) - 2016) was on the development of a nowcasting system for risk management and transnational warnings in Central Europe. The successful cooperation between scientists and civil protection agencies gained in INCA-CE encouraged a follow-up project called PROFORCE (Bridging of Probabilistic Forecasts and Civil Protection). It was launched in December 2013 and was co-funded by the European Commission – DG ECHO – Humanitarian Aid and Civil Protection. The main objective of PROFORCE was to improve preparedness and decision making procedures in civil protection agencies by building an innovative seamless probabilistic forecast system. This system provides weather forecasts and the corresponding forecast uncertainties in a seamless way from several days ahead with lower spatial resolution down to the nowcasting range with very high resolution. The probabilistic information from the numerical models is especially tailored to the needs of the individual end-users and is illustrated on a user-friendly web-portal. Warning thresholds and impact assessment were defined in a close cooperation between scientists and civil protection users. The seamless system merges four different ensemble systems which have their own role in the final system depending on the nature of the predicted weather event and the forecast range. The seamless actions and the information exchange between meteorologists and civil protection staff are illustrated in the figure below.

FEATURED EXPERT

Marion Mittermaier, had since 2014, co-chaired the WWRP/WGNE Joint Working Group on Forecast Verification Research with Laurie Wilson (formerly of ECCC). Her under-graduate background is in Applied Mathematics, Meteorology and Statistics and she completed her PhD at the University of Reading (2003), where her dissertation was on exploiting the synergy between model forecasts and radar. Marion started her career at the South African Weather Service in 1995 working on analysing aircraft in-situ observations of cloud-aerosol interactions, and microphysical processes in thunderstorms, storm dynamics, and hydrometeorology. In February 2004, she joined the UK Met Office (UKMO) starting work in the Mesoscale Model Development group. Since late 2008, she has led one of the verification teams at the UKMO responsible for diagnosing systematic behaviors in the Met Office modelling systems and finding new and novel ways of assessing the UKMO forecasts. Marion's current focus is considering the impact of observation uncertainty on verification metrics. She is also involved in shaping a future post-processing strategy and ensuring that the verification and post-processing are better linked to maximize future forecast improvements. Marion currently leads the "Mesoscale Verification Inter-Comparison over Complex Terrain" (MesoVICT) an international community project and together with other verification experts investigates quantifying observation uncertainty, and how to incorporate this into spatial verification methods. Known to her colleagues for her infectious energy, Marion is also a member of the WMO Commission for Basic Systems Task Team on global surface verification and the verification sub-group to the European Centre for Medium Range Weather Forecasts Technical Advisory Committee. It was thus not a surprise, that in November 2015, Marion was awarded the prestigious L G Groves Memorial Prize for Meteorology for her significant work in the field of verification. Her WWRP family congratulates Marion for this well-deserved recognition and for her outstanding contribution to the science of meteorology.